Desulfurization of Diesel Fuel by Extraction with (BF4)

The extractive removal of sulfur compounds (S-compounds) from Dongying and Liaohe diesel fuels with (BF4) - -based ionic liquids were systematically investigated. The results show that the absorption capacity of an ionic liquid for the S-compounds in diesel fuels relies on its structure and its size. In the case of the two exam- ined diesel fuels, both elongating the cation tail length and increasing the mass ratio of ionic liquid/diesel fuel pro- mote the desulfurization ability of the examined ionic liquids. The results also show that imidazolium-based ionic liquids display higher extraction efficiencies than pyridinium-based ionic liquids, presumably owing to the fact that the rings of the S-compounds are similar to the imidazolium head ring. With the 1︰1 mass ratio of ionic liquid/diesel fuel, the rates of the first desulfurization of Dongying and Liaohe diesel fuels using (C8mim)(BF4) amount to 29.96% and 39.76%, suggesting that (C8mim)(BF4) is a promising extractant for desulfurization of these diesel fuels. Keywords desulfurization, diesel fuel, ionic liquid